Life Sciences Commons^™

Quemando Leña En Guatemala: Salud, Sostenibilidad Y Costumbres, Sydney Underhill

World Languages and Cultures Senior Capstones

In the Central American country of Guatemala, firewood is an important fuel source. Eighty-eight percent of households in rural areas use wood stoves and open fires to cook and heat their homes. This tradition has fundamental roots in the culture and customs of Guatemala. Unfortunately, these methods contribute to air pollution. Consequently, it also results in smoke inhalation, which causes health problems. Additionally, the massive agriculture of other crops decreases the amount of firewood available to these households, affecting the sustainability of the resource. Some communities resist changing their use of firewood due to the profound nature that firewood holds …

Proposing Urban Agroforestry Designs For Lincoln, Nebraska: A Model From Berlin, Germany, Noah Johnson

Honors Theses

Given the threat of a worsening climate crisis, there is a strong need for community and ecosystem resilience. Diverse urban agroforestry systems have the potential to accomplish both and meet many of the objectives outlined in the city of Lincoln, Nebraska’s climate action plan. Additionally, Berlin, Germany could provide an effective model for Lincoln in this regard given the city’s extensive history of established urban agroforestry systems. The objective of this study then is to develop a design for an urban agroforestry site modeled on Berlin’s allotment gardens and tailored to Lincoln’s needs. The methods for creating this design included …

Dendrochronological Analysis Of The Duncan Tavern, Paris, Kentucky, Usa, Delaney Ballard, Maegen Rochner

Undergraduate Research Events

Duncan Tavern is a historical structure located at 323 High Street in Paris, Kentucky in Bourbon County. The structure currently serves as the headquarters for the Kentucky Society of the Daughters of the American Revolution (KSDAR). KSDAR maintains that Duncan Tavern was originally built in the mid-1790s; the land was purchased in 1792 by Joseph Duncan, a civilian armorer in the Revolutionary War. Although Duncan Tavern has been listed on the National Register of Historical Places since 1973, a dendrochronological study of this structure was requested to quantitatively examine the legitimacy of archival and anecdotal claims about the construction history. …

Tremblings, May 2024, Western Aspen Alliance

Tremblings

Climate change insurance: planting aspen seedlings as fuel breaks

Catherine Schloegel, Program Manager, The Nature Conservancy, Boulder, Colorado

Jordan Mead, Resource Specialist, Summit County Open Space and Trails Department, Frisco, Colorado

As climate impacts accelerate, mountain communities living near forested areas across the West will be at increasing risk of more frequent wildfires. To protect neighborhoods from high-severity wildfires, land managers frequently clear strips of forest around homes and roads. We examined the potential to plant true aspen seedlings in these fuel breaks to increase habitat diversity while maintaining a reduced risk of wildfire. Historically, aspen has acted as a …

Impact Of Changing Climate On Bryophyte Contributions To Terrestrial Water, Carbon, And Nitrogen Cycles, Mandy L. Slate, Anita Antoninka, Lydia Bailey, Monica B. Berdugo, Des A. Callaghan, Mariana Cárdenas, Matthew W. Chmielewski, Nicole J. Fenton, Hannah Holland-Moritz, Samantha Hopkins, Mélanie Jean, Bier Ekaphan Kraichak, Zoë Lindo, Amelia Merced, Tobi Oke, Daniel Stanton, Julia E. Stuart, Daniel Tucker, Kirsten K. Coe

Michigan Tech Publications, Part 2

Bryophytes, including the lineages of mosses, liverworts, and hornworts, are the second-largest photoautotroph group on Earth. Recent work across terrestrial ecosystems has highlighted how bryophytes retain and control water, fix substantial amounts of carbon (C), and contribute to nitrogen (N) cycles in forests (boreal, temperate, and tropical), tundra, peatlands, grasslands, and deserts. Understanding how changing climate affects bryophyte contributions to global cycles in different ecosystems is of primary importance. However, because of their small physical size, bryophytes have been largely ignored in research on water, C, and N cycles at global scales. Here, we review the literature on how bryophytes …

An Ecology Against The Right. Learning Uncertainty And Humility From Ecosystems, Pierre L. Ibisch, Mona Eikel-Pohen, Elias Iceman, Jake Snelling

Languages, Literatures, and Linguistics - All Scholarship

This article is a translation from the German to English. The title of the original is:

Ibisch, P.L. (2020): Eine Ökologie gegen rechts. Von Ökosystemen Unsicherheit und Demut lernen. In: Leitschuh, H., A. Brunnengräber, P.L. Ibisch, R. Loske, M. Müller, J. Sommer & E.-U. v. Weizsäcker (eds. J. Sommer, P.L. Ibisch, A. Brunnengräber): Ökologie und Heimat. Jahrbuch Ökologie 2021. Hirzel-Verlag, Stuttgart, 191-205.

Seasonal And Species-Level Water-Use Strategies And Groundwater Dependence In Dryland Riparian Woodlands During Extreme Drought, Jared Williams, John C. Stella, Michael Bliss Singer, Adam M. Lambert, Steve L. Voelker, John E. Drake, Jonathan M. Friedman, Lissa Pelletier, Li Kui, Dar A. Roberts

Michigan Tech Publications, Part 2

Drought-induced groundwater decline and warming associated with climate change are primary threats to dryland riparian woodlands. We used the extreme 2012–2019 drought in southern California as a natural experiment to assess how differences in water-use strategies and groundwater dependence may influence the drought susceptibility of dryland riparian tree species with overlapping distributions. We analyzed tree-ring stable carbon and oxygen isotopes collected from two cottonwood species (Populus trichocarpa and P. fremontii) along the semi-arid Santa Clara River. We also modeled tree source water δ18O composition to compare with observed source water δ18O within the floodplain to infer patterns of groundwater reliance. …

Non-Native Rhizophora Mangle As Sinks For Coastal Contamination On Moloka’I, Hawai’I, Geoffrey Szafranski, Elise F. Granek, Michelle L. Hladik, Mia Hackett

Environmental Science and Management Faculty Publications and Presentations

Coastal mangrove forests provide a suite of environmental services, including sequestration of anthropogenic contamination. Yet, research lags on the environmental fate and potential human health risks of mangrove-sequestered contaminants in the context of mangrove removal for development and range shifts due to climate change. To address this, we conducted a study on Moloka'i, Hawai'i, comparing microplastic and pesticide contamination in coastal compartments both at areas modified by non-native red mangroves (Rhizophora mangle) and unmodified, open coastline. Sediment, porewater, and mangrove plant tissues were collected to quantify microplastic and pesticide concentrations across ecosystem type. Average microplastics were similar between …

Changing The Culture Of Ecology From The Ground Up, Elsa Abs, Moira Hough

Michigan Tech Publications, Part 2

We are two early career soil ecologists in academia who entered the field of soil ecology with the goal of studying soil-climate feedbacks to make meaningful contributions to climate change mitigation. Although our training and research extensively focused on the effects of climate change on soil ecosystems, we were not trained during our PhD nor incentivized as postdocs to work on solutions for climate change mitigation. So the question we ask here is: Given the consensus among ecologists about the urgency of the climate crisis, why is our field not promoting more solutions-oriented research in training and practice? In this …

Responses Of Vascular Plant Fine Roots And Associated Microbial Communities To Whole-Ecosystem Warming And Elevated Co2 In Northern Peatlands, Katherine Duchesneau, Camille E. Defrenne, Caitlin Petro, Avni Malhotra, Jessica A.M. Moore, Joanne Childs, Paul J. Hanson, Colleen M. Iversen, Joel E. Kostka

Michigan Tech Publications, Part 2

Warming and elevated CO2 (eCO2) are expected to facilitate vascular plant encroachment in peatlands. The rhizosphere, where microbial activity is fueled by root turnover and exudates, plays a crucial role in biogeochemical cycling, and will likely at least partially dictate the response of the belowground carbon cycle to climate changes. We leveraged the Spruce and Peatland Responses Under Changing Environments (SPRUCE) experiment, to explore the effects of a whole-ecosystem warming gradient (+0°C to 9°C) and eCO2 on vascular plant fine roots and their associated microbes. We combined trait-based approaches with the profiling of fungal and prokaryote communities in plant roots …

Shifting The Language Of ‘Invasion’ Ecology: Two-Eyed Seeing As A Framework For Discourse Regarding Introduced Species, Shelby Nicole Lane-Clark, Valoree Gagnon, Tara Bal

Michigan Tech Publications, Part 2

Discourse used in the field of invasion ecology has significant impacts on society's perception, yet communication related to “invasives” is rife with problematic, exclusionary language. We provide potential solutions, including a repositioned perspective that may facilitate better relationships with the natural world by applying the two-eyed seeing framework. Our discussion calls for a paradigm shift for deeper understandings of human and more-than-human relationships. Ultimately, we advocate for respectful, considerate, and intentional language and stewardship.

Toward A Coordinated Understanding Of Hydro-Biogeochemical Root Functions In Tropical Forests For Application In Vegetation Models, Daniela F. Cusack, Bradley Christoffersen, Chris M. Smith-Martin, Kelly M. Andersen, Amanda L. Cordeiro, Katrin Fleischer, S. Joseph Wright, Nathaly R. Guerrero-Ramírez, Laynara F. Lugli, Lindsay A. Mcculloch, Mareli Sanchez-Julia, Sarah A. Batterman, Caroline Dallstream, Claire Fortunel, Laura Toro, Lucia Fuchslueger, Michelle Y. Wong, Daniela Yaffar, Joshua B. Fisher, Marie Arnaud, Lee H. Dietterich, Shalom D. Addo-Danso, Oscar J. Valverde-Barrantes, Monique Weemstra, Jing Cheng Ng, Richard J. Norby

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Tropical forest root characteristics and resource acquisition strategies are underrepresented in vegetation and global models, hampering the prediction of forest–climate feedbacks for these carbon-rich ecosystems. Lowland tropical forests often have globally unique combinations of high taxonomic and functional biodiversity, rainfall seasonality, and strongly weathered infertile soils, giving rise to distinct patterns in root traits and functions compared with higher latitude ecosystems. We provide a roadmap for integrating recent advances in our understanding of tropical forest belowground function into vegetation models, focusing on water and nutrient acquisition. We offer comparisons of recent advances in empirical and model understanding of root characteristics …

A Flexible Inventory Of Survey Items For Environmental Concepts Generated Via Special Attention To Content Validity And Item Response Theory, John A. Vucetich, Jeremy T. Bruskotter, Benjamin Ghasemi, Claire E. Rapp, Michael Paul Nelson, Kristina M. Slagle

Michigan Tech Publications, Part 2

We demonstrate how many important measures of belief about the environmental suffer from poor content validity and inadequate conceptual breadth (dimensionality). We used scholarship in environmental science and philosophy to propose a list of 13 environmental concepts that can be held as beliefs. After precisely articulating the concepts, we developed 85 trial survey items that emphasized content validity for each concept. The concepts’ breadth and the items’ content validity were aided by scrutiny from 17 knowledgeable critics. We administered the trial items to 449 residents of the United States and used item response theory to reduce the 85 trial items …

Land Use Change And Forest Management Effects On Soil Carbon Stocks In The Northeast U.S., Lucas E. Nave, Kendall Delyser, Grant M. Domke, Scott M. Holub, Maria K. Janowiak, Adrienne B. Keller, Matthew P. Peters, Kevin A. Solarik, Brian F. Walters, Christopher W. Swanston

Michigan Tech Publications, Part 2

Background: In most regions and ecosystems, soils are the largest terrestrial carbon pool. Their potential vulnerability to climate and land use change, management, and other drivers, along with soils’ ability to mitigate climate change through carbon sequestration, makes them important to carbon balance and management. To date, most studies of soil carbon management have been based at either large or site-specific scales, resulting in either broad generalizations or narrow conclusions, respectively. Advancing the science and practice of soil carbon management requires scientific progress at intermediate scales. Here, we conducted the fifth in a series of ecoregional assessments of the effects …

Author Correction: The Flying Spider-Monkey Tree Fern Genome Provides Insights Into Fern Evolution And Arborescence (Nature Plants, (2022), 8, 5, (500-512), 10.1038/S41477-022-01146-6), Xiong Huang, Wenling Wang, Ting Gong, David Wickell, Li Yaung Kuo, Xingtan Zhang, Jialong Wen, Hoon Kim, Fachuang Lu, Hansheng Zhao, Song Chen, Hui Li, Wenqi Wu, Changjiang Yu, Su Chen, Wei Fan, Shuai Chen, Xiuqi Bao, Li Li, Dan Zhang, Longyu Jiang, Dipak Khadka, Xiaojing Yan, Zhenyang Liao, Gongke Zhou, Yalong Guo, John Ralph, Ronald R. Sederoff, Hairong Wei, Ping Zhu, Fay Wei Li

Michigan Tech Publications, Part 2

Correction to: Nature Plantshttps://doi.org/10.1038/s41477-022-01146-6, published online 9 May 2022. In the version of the article initially published, Dipak Khadka, who collected the samples in Nepal, was thanked in the Acknowledgements instead of being listed as an author. His name and affiliation (GoldenGate International College, Tribhuvan University, Battisputali, Kathmandu, Nepal) have been added to the authorship in the HTML and PDF versions of the article.

Oystershell Scale (Hemiptera: Diaspididae) Population Growth, Spread, And Phenology On Aspen In Arizona, Usa, Connor D. Crouch, Richard W. Hofstetter, Amanda M. Grady, Nylah N.S. Edwards, Kristen M. Waring

Aspen Bibliography

Oystershell scale (OSS; Lepidosaphes ulmi L.) is an invasive insect that threatens sustainability of aspen (Populus tremuloides Michx.) in the southwestern United States. OSS invasions have created challenges for land managers tasked with maintaining healthy aspen ecosystems for the ecological, economic, and aesthetic benefits they provide. Active management is required to suppress OSS populations and mitigate damage to aspen ecosystems, but before management strategies can be implemented, critical knowledge gaps about OSS biology and ecology must be filled. This study sought to fill these gaps by addressing 3 questions: (i) What is the short-term rate of aspen mortality in …

Pile Burning After Conifer Removal From Aspen Stands Affects Tree Mortality, Regeneration, And Understory Recovery, John-Pascal Berrill, Christa M. Dagley, Yoon G. Kim, J. Morgan Varner

Aspen Bibliography

Quaking aspen (Populus tremuloides Michx.) stands throughout the western United States provide valuable ecosystem services but can be lost via succession from aspen to conifer. Forest managers are cutting conifers, but disposal of cut wood can be challenging in remote or sensitive areas. Piling and burning is being tested within aspen stands but ecosystem responses to this treatment are understudied. We assessed aspen tree mortality, tree regeneration, and understory vegetation after forest restoration thinning followed by pile burning in seven aspen-conifer stands around Lake Tahoe, California and Nevada, USA. Pile burning was conducted after cut wood had dried (1.5–7.5 …

Greater Sage-Grouse Brood Locations On Parker Mountain Utah 1998-2009, David Dahlgren

Browse all Datasets

Species of conservation concern are often habitat specialists, posing significant risk to those species when specific plant communities are threatened. Despite this, practitioners habitually focus conservation efforts on these singular communities, while ignoring ecological mechanisms that explain the wildlife-plant relationships. In doing so, practitioners may overlook alternative vegetation communities that could maintain wildlife populations under alternative conditions (e.g., climate change). Here, we term these areas surrogate habitat, defined as "vegetation communities or resource sites that provide similar critical resources to conventional sites," and assess their potential for conservation using a case-study of Greater sage-grouse (Centrocercus urophasianus) on Parker Mountain, Utah …

Deciphering The Intricate Hierarchical Gene Regulatory Network: Unraveling Multi-Level Regulation And Modifications Driving Secondary Cell Wall Formation, Zhigang Wei, Hairong Wei

Michigan Tech Publications, Part 2

Wood quality is predominantly determined by the amount and the composition of secondary cell walls (SCWs). Consequently, unraveling the molecular regulatory mechanisms governing SCW formation is of paramount importance for genetic engineering aimed at enhancing wood properties. Although SCW formation is known to be governed by a hierarchical gene regulatory network (HGRN), our understanding of how a HGRN operates and regulates the formation of heterogeneous SCWs for plant development and adaption to ever-changing environment remains limited. In this review, we examined the HGRNs governing SCW formation and highlighted the significant key differences between herbaceous Arabidopsis and woody plant poplar. We …

Animal Conservation In St. Louis, Kate O'Sullivan

Undergraduate Research Symposium

St. Louis has a multitude of organizations involved in the natural sciences. But how many of them actually contribute towards animal conservation? The St. Louis Zoo is an organization that focuses a lot of its effort on presentation, so how does that impact the funds that go towards actually saving the animals? I plan to dive into the different animal-based organizations in St. Louis and its surrounding areas, as well as discuss the positives and negatives of each organization. Furthermore, I will provide examples from several sources that I have been reviewing all year to support my claims. I plan …

Aspen And Spruce Densities Affect Tree Size, Future Stand Volume, And Aboveground Carbon Following Precommercial Thinning, Philip G. Comeau, Mike Bokalo

Aspen Bibliography

Data collected over a 30-year period from an experiment replicated across 21 locations in western Canada are used to explore the effects of precommercial thinning of trembling aspen to a range of densities in combination with three initial white spruce densities on tree growth and stand dynamics. Increasing differentiation amongst the 15 treatments was observed with age after thinning for both spruce and aspen responses. Spruce height and diameter declined with increasing aspen density. At age 10 spruce diameter with no aspen was 1.5× that of spruce in unthinned while it was 2.6× that of spruce in unthinned at age …

Perianth Evolution And Implications For Generic Delimitation In The Eucalypts (Myrtaceae), Including The Description Of The New Genus, Blakella, Michael D. Crisp, Bui Q. Minh, Bokyung Choi, Robert D. Edwards, James Hereward, Carsten Kulheim, Yen Po Lin, Karen Meusemann, Andrew H. Thornhill, Alicia Toon, Lyn G. Cook

Michigan Tech Publications, Part 2

Eucalypts (Myrtaceae tribe Eucalypteae) are currently placed in seven genera. Traditionally, Eucalyptus was defined by its operculum, but when phylogenies placed Angophora, with free sepals and petals, as sister to the operculate bloodwood eucalypts, the latter were segregated into a new genus, Corymbia. Yet, generic delimitation in the tribe Eucalypteae remains uncertain. Here, we address these problems using phylogenetic analysis with the largest molecular data set to date. We captured 101 low-copy nuclear exons from 392 samples representing 266 species. Our phylogenetic analysis used maximum likelihood (IQtree) and multispecies coalescent (Astral). At two nodes critical to generic delimitation, we tested …

Tracing The Maternal Line In Glacial-Interglacial Migrations Of Populus Tremuloides: Finding Trees For Future Sustainable Forests By Searching In The Past, Luke R. Tembrock, Frida A. Zink, Guozhe Zhang, Andrea Schuhmann, Cuihua Gu, Zhiqiang Wu

Aspen Bibliography

Maintaining and planting sustainable forests is fundamental in perpetuating the essential functions of these ecosystems. A central aspect of managing forests for future resilience is the consideration of past migration and evolution of trees using genetic and genomic data to ensure that functionally appropriate diversity is conserved and utilized. In our study, we generated and compared genetic and genomic data from the plastome to better understand phylogeography and molecular evolution in the tree species Populus tremuloides (aspen). With these analyses, we found evidence of divergence and migration between northern and southern sites. Additionally, evidence of deep incomplete plastome sorting across …

Non-Invasive Methods For Monitoring Weasels: Emerging Technologies And Priorities For Future Research, David S. Jachowski, Scott M. Bergeson, Stacy Cotey, Elizabeth Croose, Tim R. Hofmeester, Jenny Macpherson, Et Al.

Michigan Tech Publications, Part 2

Weasels (genus Mustela and Neogale) are of management concern as declining native species in some regions and invasive species in others. Regardless of the need to conserve or remove weasels, there is increasingly a need to use non-invasive monitoring methods to assess population trends. We conducted a literature review and held the first ever International Weasel Monitoring Symposium to synthesise information on historical and current non-invasive monitoring techniques for weasels. We also explored current limitations, opportunities, and areas of development to guide future research and long-term monitoring. Our literature search revealed that in the past 20 years, camera traps were …

Engagement For Life's Sake: Reflections On Partnering And Partnership With Rural Tribal Nations☆, Chelsea Schelly, Valoree Gagnon, Kathleen Brosemer, Kristin Arola

Michigan Tech Publications, Part 2

In this paper, we reflect on our collective experiences engaging with Anishinaabe Tribal Nations in the Great Lakes region to support Tribal sovereignty in decision-making for food, energy, and water (FEW) systems. In these diverse experiences, we find common lessons. The first set of lessons contributes new empirical knowledge regarding the challenges and opportunities that rural Great Lakes Tribal Nations navigate for enacting sovereignty in decision-making. Our experiences illustrate that while Tribal Nations benefit from a broad and deep commitment to sovereignty and many cultural strengths, they are often challenged by shortages in administrative capacity; technical support; and embeddedness in …

Persistent Net Release Of Carbon Dioxide And Methane From An Alaskan Lowland Boreal Peatland Complex, Eugénie S. Euskirchen, Colin W. Edgar, Evan Kane, Mark P. Waldrop, Rebecca B. Neumann, Kristen L. Manies, Thomas A. Douglas, Catherine Dieleman, Miriam C. Jones, Merritt R. Turetsky

Michigan Tech Publications, Part 2

Permafrost degradation in peatlands is altering vegetation and soil properties and impacting net carbon storage. We studied four adjacent sites in Alaska with varied permafrost regimes, including a black spruce forest on a peat plateau with permafrost, two collapse scar bogs of different ages formed following thermokarst, and a rich fen without permafrost. Measurements included year-round eddy covariance estimates of net carbon dioxide (CO2), mid-April to October methane (CH4) emissions, and environmental variables. From 2011 to 2022, annual rainfall was above the historical average, snow water equivalent increased, and snow-season duration shortened due to later snow return. Seasonally thawed active …

Supporting Information For “Using Drones Equipped With Thermal Cameras To Locate And Count Quail Individuals And Coveys: A Case Study Using Northern Bobwhite Colinus Virginianus In Mississippi, Usa”, Jared A. Elmore

Publications

Drone flights were conducted over bobwhite individuals and coveys and information was collected on the date, time of flight, number of individuals estimated in the covey, and number of individuals flushed from the covey (i.e., actual number of individuals). We also report season of flight and the thermal sensor used for each flight. NA denotes that flush or capture was not attempted.

Stabilization Of Pfas-Contaminated Soil With Sewage Sludge- And Wood-Based Biochar Sorbents, Erlend Sørmo, Clara Benedikte Mader Lade, Julie Zhang, Alexandros G. Asimakopoulos, Geir Wold Åsli, Michel Hubert, Aleksandar I. Goranov, Hans Peter H. Arp, Gerard Cornelissen

Chemistry & Biochemistry Faculty Publications

Sustainable and effective remediation technologies for the treatment of soil contaminated with per- and polyfluoroalkyl substances (PFAS) are greatly needed. This study investigated the effects of waste-based biochars on the leaching of PFAS from a sandy soil with a low total organic carbon content (TOC) of 0.57 ± 0.04% impacted by PFAS from aqueous film forming foam (AFFF) dispersed at a former fire-fighting facility. Six different biochars (pyrolyzed at 700–900°C) were tested, made from clean wood chips (CWC), waste timber (WT), activated waste timber (aWT), two digested sewage sludges (DSS-1 and DSS-2) and de-watered raw sewage sludge (DWSS). Up-flow column …

Assessing Changing Carbon Pool Dynamics And Species Composition In A Pennsylvania Broadleaf Forest Fragment, Kyleigh Levinsky, Jessica L. Schedlbauer

Sustainability Research & Creative Activities Grants Reports

Temperate broadleaf forests are pivotal to the global carbon cycle, Representing 37% of the global forest carbon pool (Pan et al 2011). • Maintaining compositional diversity in temperate broadleaf forests, such as the Gordon Natural Area (GNA) is critical to maintaining ecosystem services, such as carbon sequestration. • Pressures from native and non-native herbivores threaten the biodiversity of temperate broadleaf forests in the United States (Ghandi et al. 2010). The introduction of non-native insects such as the emerald ash borer (Argrilus planipennis), as well as the overpopulation of white-tailed deer (Odocoileus virginianus) has led to declines in some tree species. …

Long Oligodeoxynucleotides: Chemical Synthesis, Isolation Via Catching-By-Polymerization, Verification Via Sequencing, And Gene Expression Demonstration, Yipeng Yin, Reed Arneson, Alexander Apostle, Adikari M.D.N. Eriyagama, Komal Chillar, Emily Burke, Martina Jahfetson, Yinan Yuan, Shiyue Fang

Michigan Tech Publications, Part 2

Long oligodeoxynucleotides (ODNs) are segments of DNAs having over one hundred nucleotides (nt). They are typically assembled using enzymatic methods such as PCR and ligation from shorter 20 to 60 nt ODNs produced by automated de novo chemical synthesis. While these methods have made many projects in areas such as synthetic biology and protein engineering possible, they have various drawbacks. For example, they cannot produce genes and genomes with long repeats and have difficulty to produce sequences containing stable secondary structures. Here, we report a direct de novo chemical synthesis of 400 nt ODNs, and their isolation from the complex …